Extract OAuth2AccessTokenFetcher interface.

google_apis/gaia/oauth2_access_token_fetcher.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "google_apis/gaia/oauth2_access_token_fetcher.h"
 
-#include <algorithm>
-#include <string>
-#include <vector>
+OAuth2AccessTokenFetcher::OAuth2AccessTokenFetcher(
+    OAuth2AccessTokenConsumer* consumer)
+    : consumer_(consumer) {}
 
-#include "base/json/json_reader.h"
-#include "base/metrics/histogram.h"
-#include "base/metrics/sparse_histogram.h"
-#include "base/strings/string_util.h"
-#include "base/strings/stringprintf.h"
-#include "base/time/time.h"
-#include "base/values.h"
-#include "google_apis/gaia/gaia_urls.h"
-#include "google_apis/gaia/google_service_auth_error.h"
-#include "net/base/escape.h"
-#include "net/base/load_flags.h"
-#include "net/http/http_status_code.h"
-#include "net/url_request/url_fetcher.h"
-#include "net/url_request/url_request_context_getter.h"
-#include "net/url_request/url_request_status.h"
+OAuth2AccessTokenFetcher::~OAuth2AccessTokenFetcher() {}
 
-using net::ResponseCookies;
-using net::URLFetcher;
-using net::URLFetcherDelegate;
-using net::URLRequestContextGetter;
-using net::URLRequestStatus;
-
-namespace {
-static const char kGetAccessTokenBodyFormat[] =
-    "client_id=%s&"
-    "client_secret=%s&"
-    "grant_type=refresh_token&"
-    "refresh_token=%s";
-
-static const char kGetAccessTokenBodyWithScopeFormat[] =
-    "client_id=%s&"
-    "client_secret=%s&"
-    "grant_type=refresh_token&"
-    "refresh_token=%s&"
-    "scope=%s";
-
-static const char kAccessTokenKey[] = "access_token";
-static const char kExpiresInKey[] = "expires_in";
-static const char kErrorKey[] = "error";
-
-// Enumerated constants for logging server responses on 400 errors, matching
-// RFC 6749.
-enum OAuth2ErrorCodesForHistogram {
-   OAUTH2_ACCESS_ERROR_INVALID_REQUEST = 0,
-   OAUTH2_ACCESS_ERROR_INVALID_CLIENT,
-   OAUTH2_ACCESS_ERROR_INVALID_GRANT,
-   OAUTH2_ACCESS_ERROR_UNAUTHORIZED_CLIENT,
-   OAUTH2_ACCESS_ERROR_UNSUPPORTED_GRANT_TYPE,
-   OAUTH2_ACCESS_ERROR_INVALID_SCOPE,
-   OAUTH2_ACCESS_ERROR_UNKNOWN,
-   OAUTH2_ACCESS_ERROR_COUNT
-};
-
-OAuth2ErrorCodesForHistogram OAuth2ErrorToHistogramValue(
-    const std::string& error) {
-  if (error == "invalid_request")
-    return OAUTH2_ACCESS_ERROR_INVALID_REQUEST;
-  else if (error == "invalid_client")
-    return OAUTH2_ACCESS_ERROR_INVALID_CLIENT;
-  else if (error == "invalid_grant")
-    return OAUTH2_ACCESS_ERROR_INVALID_GRANT;
-  else if (error == "unauthorized_client")
-    return OAUTH2_ACCESS_ERROR_UNAUTHORIZED_CLIENT;
-  else if (error == "unsupported_grant_type")
-    return OAUTH2_ACCESS_ERROR_UNSUPPORTED_GRANT_TYPE;
-  else if (error == "invalid_scope")
-    return OAUTH2_ACCESS_ERROR_INVALID_SCOPE;
-
-  return OAUTH2_ACCESS_ERROR_UNKNOWN;
-}
-
-static GoogleServiceAuthError CreateAuthError(URLRequestStatus status) {
-  CHECK(!status.is_success());
-  if (status.status() == URLRequestStatus::CANCELED) {
-    return GoogleServiceAuthError(GoogleServiceAuthError::REQUEST_CANCELED);
-  } else {
-    DLOG(WARNING) << "Could not reach Google Accounts servers: errno "
-                  << status.error();
-    return GoogleServiceAuthError::FromConnectionError(status.error());
-  }
-}
-
-static URLFetcher* CreateFetcher(URLRequestContextGetter* getter,
-                                 const GURL& url,
-                                 const std::string& body,
-                                 URLFetcherDelegate* delegate) {
-  bool empty_body = body.empty();
-  URLFetcher* result = net::URLFetcher::Create(
-      0, url,
-      empty_body ? URLFetcher::GET : URLFetcher::POST,
-      delegate);
-
-  result->SetRequestContext(getter);
-  result->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
-                       net::LOAD_DO_NOT_SAVE_COOKIES);
-  // Fetchers are sometimes cancelled because a network change was detected,
-  // especially at startup and after sign-in on ChromeOS. Retrying once should
-  // be enough in those cases; let the fetcher retry up to 3 times just in case.
-  // http://crbug.com/163710
-  result->SetAutomaticallyRetryOnNetworkChanges(3);
-
-  if (!empty_body)
-    result->SetUploadData("application/x-www-form-urlencoded", body);
-
-  return result;
-}
-}  // namespace
-
-OAuth2AccessTokenFetcher::OAuth2AccessTokenFetcher(
-    OAuth2AccessTokenConsumer* consumer,
-    URLRequestContextGetter* getter)
-    : consumer_(consumer),
-      getter_(getter),
-      state_(INITIAL) { }
-
-OAuth2AccessTokenFetcher::~OAuth2AccessTokenFetcher() { }
-
-void OAuth2AccessTokenFetcher::CancelRequest() {
-  fetcher_.reset();
-}
-
-void OAuth2AccessTokenFetcher::Start(const std::string& client_id,
-                                     const std::string& client_secret,
-                                     const std::string& refresh_token,
-                                     const std::vector<std::string>& scopes) {
-  client_id_ = client_id;
-  client_secret_ = client_secret;
-  refresh_token_ = refresh_token;
-  scopes_ = scopes;
-  StartGetAccessToken();
-}
-
-void OAuth2AccessTokenFetcher::StartGetAccessToken() {
-  CHECK_EQ(INITIAL, state_);
-  state_ = GET_ACCESS_TOKEN_STARTED;
-  fetcher_.reset(CreateFetcher(
-      getter_,
-      MakeGetAccessTokenUrl(),
-      MakeGetAccessTokenBody(
-          client_id_, client_secret_, refresh_token_, scopes_),
-      this));
-  fetcher_->Start();  // OnURLFetchComplete will be called.
-}
-
-void OAuth2AccessTokenFetcher::EndGetAccessToken(
-    const net::URLFetcher* source) {
-  CHECK_EQ(GET_ACCESS_TOKEN_STARTED, state_);
-  state_ = GET_ACCESS_TOKEN_DONE;
-
-  URLRequestStatus status = source->GetStatus();
-  int histogram_value = status.is_success() ? source->GetResponseCode() :
-                                              status.error();
-  UMA_HISTOGRAM_SPARSE_SLOWLY("Gaia.ResponseCodesForOAuth2AccessToken",
-                              histogram_value);
-  if (!status.is_success()) {
-    OnGetTokenFailure(CreateAuthError(status));
-    return;
-  }
-
-  switch (source->GetResponseCode()) {
-    case net::HTTP_OK:
-      break;
-    case net::HTTP_FORBIDDEN:
-    case net::HTTP_INTERNAL_SERVER_ERROR:
-      // HTTP_FORBIDDEN (403) is treated as temporary error, because it may be
-      // '403 Rate Limit Exeeded.' 500 is always treated as transient.
-      OnGetTokenFailure(GoogleServiceAuthError(
-          GoogleServiceAuthError::SERVICE_UNAVAILABLE));
-      return;
-    case net::HTTP_BAD_REQUEST: {
-      // HTTP_BAD_REQUEST (400) usually contains error as per
-      // http://tools.ietf.org/html/rfc6749#section-5.2.
-      std::string gaia_error;
-      if (!ParseGetAccessTokenFailureResponse(source, &gaia_error)) {
-        OnGetTokenFailure(GoogleServiceAuthError(
-            GoogleServiceAuthError::SERVICE_ERROR));
-        return;
-      }
-
-      OAuth2ErrorCodesForHistogram access_error(OAuth2ErrorToHistogramValue(
-          gaia_error));
-      UMA_HISTOGRAM_ENUMERATION("Gaia.BadRequestTypeForOAuth2AccessToken",
-                                access_error, OAUTH2_ACCESS_ERROR_COUNT);
-
-      OnGetTokenFailure(access_error == OAUTH2_ACCESS_ERROR_INVALID_GRANT ?
-          GoogleServiceAuthError(
-              GoogleServiceAuthError::INVALID_GAIA_CREDENTIALS) :
-          GoogleServiceAuthError(
-              GoogleServiceAuthError::SERVICE_ERROR));
-      return;
-    }
-    default:
-      // The other errors are treated as permanent error.
-      OnGetTokenFailure(GoogleServiceAuthError(
-          GoogleServiceAuthError::INVALID_GAIA_CREDENTIALS));
-      return;
-  }
-
-  // The request was successfully fetched and it returned OK.
-  // Parse out the access token and the expiration time.
-  std::string access_token;
-  int expires_in;
-  if (!ParseGetAccessTokenSuccessResponse(
-          source, &access_token, &expires_in)) {
-    DLOG(WARNING) << "Response doesn't match expected format";
-    OnGetTokenFailure(
-        GoogleServiceAuthError(GoogleServiceAuthError::SERVICE_UNAVAILABLE));
-    return;
-  }
-  // The token will expire in |expires_in| seconds. Take a 10% error margin to
-  // prevent reusing a token too close to its expiration date.
-  OnGetTokenSuccess(
-      access_token,
-      base::Time::Now() + base::TimeDelta::FromSeconds(9 * expires_in / 10));
-}
-
-void OAuth2AccessTokenFetcher::OnGetTokenSuccess(
+void OAuth2AccessTokenFetcher::FireOnGetTokenSuccess(
     const std::string& access_token,
     const base::Time& expiration_time) {
   consumer_->OnGetTokenSuccess(access_token, expiration_time);
 }
 
-void OAuth2AccessTokenFetcher::OnGetTokenFailure(
+void OAuth2AccessTokenFetcher::FireOnGetTokenFailure(
     const GoogleServiceAuthError& error) {
-  state_ = ERROR_STATE;
   consumer_->OnGetTokenFailure(error);
 }
-
-void OAuth2AccessTokenFetcher::OnURLFetchComplete(
-    const net::URLFetcher* source) {
-  CHECK(source);
-  CHECK(state_ == GET_ACCESS_TOKEN_STARTED);
-  EndGetAccessToken(source);
-}
-
-// static
-GURL OAuth2AccessTokenFetcher::MakeGetAccessTokenUrl() {
-  return GaiaUrls::GetInstance()->oauth2_token_url();
-}
-
-// static
-std::string OAuth2AccessTokenFetcher::MakeGetAccessTokenBody(
-    const std::string& client_id,
-    const std::string& client_secret,
-    const std::string& refresh_token,
-    const std::vector<std::string>& scopes) {
-  std::string enc_client_id = net::EscapeUrlEncodedData(client_id, true);
-  std::string enc_client_secret =
-      net::EscapeUrlEncodedData(client_secret, true);
-  std::string enc_refresh_token =
-      net::EscapeUrlEncodedData(refresh_token, true);
-  if (scopes.empty()) {
-    return base::StringPrintf(
-        kGetAccessTokenBodyFormat,
-        enc_client_id.c_str(),
-        enc_client_secret.c_str(),
-        enc_refresh_token.c_str());
-  } else {
-    std::string scopes_string = JoinString(scopes, ' ');
-    return base::StringPrintf(
-        kGetAccessTokenBodyWithScopeFormat,
-        enc_client_id.c_str(),
-        enc_client_secret.c_str(),
-        enc_refresh_token.c_str(),
-        net::EscapeUrlEncodedData(scopes_string, true).c_str());
-  }
-}
-
-scoped_ptr<base::DictionaryValue> ParseGetAccessTokenResponse(
-    const net::URLFetcher* source) {
-  CHECK(source);
-
-  std::string data;
-  source->GetResponseAsString(&data);
-  scoped_ptr<base::Value> value(base::JSONReader::Read(data));
-  if (!value.get() || value->GetType() != base::Value::TYPE_DICTIONARY)
-    value.reset();
-
-  return scoped_ptr<base::DictionaryValue>(
-      static_cast<base::DictionaryValue*>(value.release()));
-}
-
-// static
-bool OAuth2AccessTokenFetcher::ParseGetAccessTokenSuccessResponse(
-    const net::URLFetcher* source,
-    std::string* access_token,
-    int* expires_in) {
-  CHECK(access_token);
-  scoped_ptr<base::DictionaryValue> value = ParseGetAccessTokenResponse(
-      source);
-  if (value.get() == NULL)
-    return false;
-
-  return value->GetString(kAccessTokenKey, access_token) &&
-      value->GetInteger(kExpiresInKey, expires_in);
-}
-
-// static
-bool OAuth2AccessTokenFetcher::ParseGetAccessTokenFailureResponse(
-    const net::URLFetcher* source,
-    std::string* error) {
-  CHECK(error);
-  scoped_ptr<base::DictionaryValue> value = ParseGetAccessTokenResponse(
-      source);
-  if (value.get() == NULL)
-    return false;
-  return value->GetString(kErrorKey, error);
-}